mirror of
https://github.com/friendica/friendica
synced 2024-12-27 08:02:19 +00:00
315 lines
12 KiB
Markdown
315 lines
12 KiB
Markdown
PHP Markdown
|
||
============
|
||
|
||
PHP Markdown Lib 1.4.1 - 4 May 2013
|
||
|
||
by Michel Fortin
|
||
<http://michelf.ca/>
|
||
|
||
based on Markdown by John Gruber
|
||
<http://daringfireball.net/>
|
||
|
||
|
||
Introduction
|
||
------------
|
||
|
||
This is a library package that includes the PHP Markdown parser and its
|
||
sibling PHP Markdown Extra with additional features.
|
||
|
||
Markdown is a text-to-HTML conversion tool for web writers. Markdown
|
||
allows you to write using an easy-to-read, easy-to-write plain text
|
||
format, then convert it to structurally valid XHTML (or HTML).
|
||
|
||
"Markdown" is actually two things: a plain text markup syntax, and a
|
||
software tool, originally written in Perl, that converts the plain text
|
||
markup to HTML. PHP Markdown is a port to PHP of the original Markdown
|
||
program by John Gruber.
|
||
|
||
* [Full documentation of the Markdown syntax](<http://daringfireball.net/projects/markdown/>)
|
||
- Daring Fireball (John Gruber)
|
||
* [Markdown Extra syntax additions](<http://michelf.ca/projects/php-markdown/extra/>)
|
||
- Michel Fortin
|
||
|
||
|
||
Requirement
|
||
-----------
|
||
|
||
This library package requires PHP 5.3 or later.
|
||
|
||
Note: The older plugin/library hybrid package for PHP Markdown and
|
||
PHP Markdown Extra is still maintained and will work with PHP 4.0.5 and later.
|
||
|
||
Before PHP 5.3.7, pcre.backtrack_limit defaults to 100 000, which is too small
|
||
in many situations. You might need to set it to higher values. Later PHP
|
||
releases defaults to 1 000 000, which is usually fine.
|
||
|
||
|
||
Usage
|
||
-----
|
||
|
||
This library package is meant to be used with class autoloading. For autoloading
|
||
to work, your project needs have setup a PSR-0-compatible autoloader. See the
|
||
included Readme.php file for a minimal autoloader setup. (If you cannot use
|
||
autoloading, see below.)
|
||
|
||
With class autoloading in place, putting the 'Michelf' folder in your
|
||
include path should be enough for this to work:
|
||
|
||
use \Michelf\Markdown;
|
||
$my_html = Markdown::defaultTransform($my_text);
|
||
|
||
Markdown Extra syntax is also available the same way:
|
||
|
||
use \Michelf\MarkdownExtra;
|
||
$my_html = MarkdownExtra::defaultTransform($my_text);
|
||
|
||
If you wish to use PHP Markdown with another text filter function
|
||
built to parse HTML, you should filter the text *after* the `transform`
|
||
function call. This is an example with [PHP SmartyPants][psp]:
|
||
|
||
use \Michelf\Markdown, \Michelf\SmartyPants;
|
||
$my_html = Markdown::defaultTransform($my_text);
|
||
$my_html = SmartyPants::defaultTransform($my_html);
|
||
|
||
All these examples are using the static `defaultTransform` static function
|
||
found inside the parser class. If you want to customize the parser
|
||
configuration, you can also instantiate it directly and change some
|
||
configuration variables:
|
||
|
||
use \Michelf\MarkdownExtra;
|
||
$parser = new MarkdownExtra;
|
||
$parser->fn_id_prefix = "post22-";
|
||
$my_html = $parser->transform($my_text);
|
||
|
||
To learn more, see the full list of [configuration variables].
|
||
|
||
[configuration variables]: http://michelf.ca/projects/php-markdown/configuration/
|
||
|
||
|
||
### Usage without an autoloader
|
||
|
||
If you cannot use class autoloading, you can still use `include` or `require`
|
||
to access the parser. To load the `\Michelf\Markdown` parser, do it this way:
|
||
|
||
require_once 'Michelf/Markdown.inc.php';
|
||
|
||
Or, if you need the `\Michelf\MarkdownExtra` parser:
|
||
|
||
require_once 'Michelf/MarkdownExtra.inc.php';
|
||
|
||
While the plain `.php` files depend on autoloading to work correctly, using the
|
||
`.inc.php` files instead will eagerly load the dependencies that would be
|
||
loaded on demand if you were using autoloading.
|
||
|
||
|
||
Public API and Versioning Policy
|
||
---------------------------------
|
||
|
||
Version numbers are of the form *major*.*minor*.*patch*.
|
||
|
||
The public API of PHP Markdown consist of the two parser classes `Markdown`
|
||
and `MarkdownExtra`, their constructors, the `transform` and `defaultTransform`
|
||
functions and their configuration variables. The public API is stable for
|
||
a given major version number. It might get additions when the minor version
|
||
number increments.
|
||
|
||
**Protected members are not considered public API.** This is unconventional
|
||
and deserves an explanation. Incrementing the major version number every time
|
||
the underlying implementation of something changes is going to give
|
||
nonessential version numbers for the vast majority of people who just use the
|
||
parser. Protected members are meant to create parser subclasses that behave in
|
||
different ways. Very few people create parser subclasses. I don't want to
|
||
discourage it by making everything private, but at the same time I can't
|
||
guarantee any stable hook between versions if you use protected members.
|
||
|
||
**Syntax changes** will increment the minor number for new features, and the
|
||
patch number for small corrections. A *new feature* is something that needs a
|
||
change in the syntax documentation. Note that since PHP Markdown Lib includes
|
||
two parsers, a syntax change for either of them will increment the minor
|
||
number. Also note that there is nothing perfectly backward-compatible with the
|
||
Markdown syntax: all inputs are always valid, so new features always replace
|
||
something that was previously legal, although generally nonsensical to do.
|
||
|
||
|
||
Bugs
|
||
----
|
||
|
||
To file bug reports please send email to:
|
||
<michel.fortin@michelf.ca>
|
||
|
||
Please include with your report: (1) the example input; (2) the output you
|
||
expected; (3) the output PHP Markdown actually produced.
|
||
|
||
If you have a problem where Markdown gives you an empty result, first check
|
||
that the backtrack limit is not too low by running `php --info | grep pcre`.
|
||
See Installation and Requirement above for details.
|
||
|
||
|
||
Development and Testing
|
||
-----------------------
|
||
|
||
Pull requests for fixing bugs are welcome. Proposed new features are
|
||
going meticulously reviewed -- taking into account backward compatibility,
|
||
potential side effects, and future extensibility -- before deciding on
|
||
acceptance or rejection.
|
||
|
||
If you make a pull request that includes changes to the parser please add
|
||
tests for what is being changed to [MDTest][] and make a pull request there
|
||
too.
|
||
|
||
[MDTest]: https://github.com/michelf/mdtest/
|
||
|
||
|
||
Donations
|
||
---------
|
||
|
||
If you wish to make a donation that will help me devote more time to
|
||
PHP Markdown, please visit [michelf.ca/donate] or send Bitcoin to
|
||
[1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH].
|
||
|
||
[michelf.ca/donate]: https://michelf.ca/donate/#!Thanks%20for%20PHP%20Markdown
|
||
[1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH]: bitcoin:1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH
|
||
|
||
|
||
Version History
|
||
---------------
|
||
|
||
Unreleased
|
||
|
||
* Added the ability to insert custom HTML attributes everywhere an extra
|
||
attribute block is allowed (links, images, headers). Credits to
|
||
Peter Droogmans for providing the implementation.
|
||
|
||
* Added a `url_filter_func` configuration variable which takes a function
|
||
that can rewrite any link or image URL to something different.
|
||
|
||
|
||
PHP Markdown Lib 1.4.1 (4 May 2014)
|
||
|
||
* The HTML block parser will now treat `<figure>` as a block-level element
|
||
(as it should) and no longer wrap it in `<p>` or parse it's content with
|
||
the as Markdown syntax (although with Extra you can use `markdown="1"`
|
||
if you wish to use the Markdown syntax inside it).
|
||
|
||
* The content of `<style>` elements will now be left alone, its content
|
||
won't be interpreted as Markdown.
|
||
|
||
* Corrected an bug where some inline links with spaces in them would not
|
||
work even when surounded with angle brackets:
|
||
|
||
[link](<s p a c e s>)
|
||
|
||
* Fixed an issue where email addresses with quotes in them would not always
|
||
have the quotes escaped in the link attribute, causing broken links (and
|
||
invalid HTML).
|
||
|
||
* Fixed the case were a link definition following a footnote definition would
|
||
be swallowed by the footnote unless it was separated by a blank line.
|
||
|
||
|
||
PHP Markdown Lib 1.4.0 (29 Nov 2013)
|
||
|
||
* Added support for the `tel:` URL scheme in automatic links.
|
||
|
||
<tel:+1-111-111-1111>
|
||
|
||
It gets converted to this (note the `tel:` prefix becomes invisible):
|
||
|
||
<a href="tel:+1-111-111-1111">+1-111-111-1111</a>
|
||
|
||
* Added backtick fenced code blocks to MarkdownExtra, originally from
|
||
Github-Flavored Markdown.
|
||
|
||
* Added an interface called MarkdownInterface implemented by both
|
||
the Markdown and MarkdownExtra parsers. You can use the interface if
|
||
you want to create a mockup parser object for unit testing.
|
||
|
||
* For those of you who cannot use class autoloading, you can now
|
||
include `Michelf/Markdown.inc.php` or `Michelf/MarkdownExtra.inc.php` (note
|
||
the `.inc.php` extension) to automatically include other files required
|
||
by the parser.
|
||
|
||
|
||
PHP Markdown Lib 1.3 (11 Apr 2013)
|
||
|
||
This is the first release of PHP Markdown Lib. This package requires PHP
|
||
version 5.3 or later and is designed to work with PSR-0 autoloading and,
|
||
optionally with Composer. Here is a list of the changes since
|
||
PHP Markdown Extra 1.2.6:
|
||
|
||
* Plugin interface for WordPress and other systems is no longer present in
|
||
the Lib package. The classic package is still available if you need it:
|
||
<http://michelf.ca/projects/php-markdown/classic/>
|
||
|
||
* Added `public` and `protected` protection attributes, plus a section about
|
||
what is "public API" and what isn't in the Readme file.
|
||
|
||
* Changed HTML output for footnotes: now instead of adding `rel` and `rev`
|
||
attributes, footnotes links have the class name `footnote-ref` and
|
||
backlinks `footnote-backref`.
|
||
|
||
* Fixed some regular expressions to make PCRE not shout warnings about POSIX
|
||
collation classes (dependent on your version of PCRE).
|
||
|
||
* Added optional class and id attributes to images and links using the same
|
||
syntax as for headers:
|
||
|
||
[link](url){#id .class}
|
||
![img](url){#id .class}
|
||
|
||
It work too for reference-style links and images. In this case you need
|
||
to put those attributes at the reference definition:
|
||
|
||
[link][linkref] or [linkref]
|
||
![img][linkref]
|
||
|
||
[linkref]: url "optional title" {#id .class}
|
||
|
||
* Fixed a PHP notice message triggered when some table column separator
|
||
markers are missing on the separator line below column headers.
|
||
|
||
* Fixed a small mistake that could cause the parser to retain an invalid
|
||
state related to parsing links across multiple runs. This was never
|
||
observed (that I know of), but it's still worth fixing.
|
||
|
||
|
||
Copyright and License
|
||
---------------------
|
||
|
||
PHP Markdown Lib
|
||
Copyright (c) 2004-2014 Michel Fortin
|
||
<http://michelf.ca/>
|
||
All rights reserved.
|
||
|
||
Based on Markdown
|
||
Copyright (c) 2003-2005 John Gruber
|
||
<http://daringfireball.net/>
|
||
All rights reserved.
|
||
|
||
Redistribution and use in source and binary forms, with or without
|
||
modification, are permitted provided that the following conditions are
|
||
met:
|
||
|
||
* Redistributions of source code must retain the above copyright
|
||
notice, this list of conditions and the following disclaimer.
|
||
|
||
* Redistributions in binary form must reproduce the above copyright
|
||
notice, this list of conditions and the following disclaimer in the
|
||
documentation and/or other materials provided with the
|
||
distribution.
|
||
|
||
* Neither the name "Markdown" nor the names of its contributors may
|
||
be used to endorse or promote products derived from this software
|
||
without specific prior written permission.
|
||
|
||
This software is provided by the copyright holders and contributors "as
|
||
is" and any express or implied warranties, including, but not limited
|
||
to, the implied warranties of merchantability and fitness for a
|
||
particular purpose are disclaimed. In no event shall the copyright owner
|
||
or contributors be liable for any direct, indirect, incidental, special,
|
||
exemplary, or consequential damages (including, but not limited to,
|
||
procurement of substitute goods or services; loss of use, data, or
|
||
profits; or business interruption) however caused and on any theory of
|
||
liability, whether in contract, strict liability, or tort (including
|
||
negligence or otherwise) arising in any way out of the use of this
|
||
software, even if advised of the possibility of such damage.
|